TOPIC A

Question 1

4 major classes of biomolecules:

Answer 1

1. Amino acids
2. Carbohydrates
3. Nucelotides
4. Lipids

Question 1

3 major bio polymers:

Answer 1

1. PROTEINS (of amino acids)- genetically encoded
2. POLYSACCHARIDES (of monosaccharies..or sugars)
3. NUCLEIC ACIDS (of nucleotides) - genetically encoded

Question 2

What dont form polymers

Answer 2

lipids

Question 3

What did Crick & Watson discover?

Answer 3

structure of double helix and theryby how it works (base pairing) DNA sequence in gene dictates sequence in mRNA strand, each triplet/codon only recognized by complimentary anti-codon in a specific tRNA charged by a specific amino acid

Question 4

What do spontaneous processes require?

Answer 4

structure of double helix and theryby how it works (base pairing) DNA sequence in gene dictates sequence in mRNA strand, each triplet/codon only recognized by complimentary anti-codon in a specific tRNA charged by a specific amino acid

Question 5

STRUCTURE OF AMINO ACIDS

Answer 5

*all share same basic structure
- central carbon/alpha carbon with 4 substituents… - side chains distinguish each
1. Alpha Amino group
2. Alpha Carboxyl group
3. Hydrogen group
4. R group

Question 6

What is molecular geometry of a basic amino acid

Answer 6

tetrahedral

Question 7

what are the two possible stereoisomers

Answer 7

d and L

Question 8

is it D or L that makes the proteins

Answer 8

L

Question 9

How many amino acids are there

Answer 9

20

Question 10

Which is the only non-chiral amino acid

Answer 10

glycine

Question 11

Which is the smallest amino acid

Answer 11

glycine

Question 12

which are the 4 cyclic amino acids

Answer 12

proline, tyrosine, tryptophan and phenyalanine

Question 13

What is an imino acid and give an example

Answer 13

imino acids have a nitrogen atom in place of one of the carbon atoms in their backbone, and lack one hydrogen for eg: proline

Question 14

Properties of carboxyl groups

Answer 14

-protonated= neutral charge
-deprotonated= negative charge

**at neutral pH, they are a negative charge (COO-)

Question 15

properties of amino groups

Answer 15

-protonated= positive charge
-deprotonated= neutral charge

*at neutral pH, they are positive charge (NH3+)

Question 16

What are the two terminuses in a polypeptide

Answer 16

N-terminus and C-terminus

Question 17

How do you read the polypeptide

Answer 17

from the N-terminus to the C-terminus

Question 18

Which amino avid under oxidation condition forms a disulfide bond?

Answer 18

Cystine

Question 19

are all side chains ionizable

Answer 19

no

Question 20

what are the ionizable side chains

Answer 20

N- terminus
C-terminus
Histide
Aspartate or Aspartic acid
Cystine
Tyrosine
Lysine
Arganine

Question 21

What reaction is the formation of a peptide bond and what does it release?

Answer 21

-releases a watermolecule
and is a condensation reaction

Question 22

Lower pka = ?

Answer 22

stronger acid

Question 23

Dipeptide

Answer 23

a peptide chain composed of 2 amino acids

Question 24

tripeptide

Answer 24

a peptide chain composed of 3 amino acids

Question 25

Oligopeptide

Answer 25

a peptide chain composed of approx 3-20 amino acids

Question 26

polypeptide

Answer 26

a peptide chain composed of many amino acids

Question 27

Protein

Answer 27

a molecule composed of one or more polypeptide chains

Question 28

What is a residue

Answer 28

- when part of a polypeptide, each amino acid is called a residue

Question 29

Characteristics of a double bonds in polypeptide chains

Answer 29

- peptide bond has 40% double bond character, therefore limited rotation - wo - has limited rotation - atoms rigidly fixed on a plane - restricts possible folding patterns of chains

Question 30

primary structure

Answer 30

- sequence of amino acid residues

Question 31

secondary structures

Answer 31

- the spatial arrangement of the polypeptide backbone

Question 32

tertiary structure

Answer 32

the three dimension structure of an entire polypeptide, including all of its sidechains

Question 33

quarternary structure

Answer 33

spatial arrangement of polypeptide chains in a protein with multiple subunits

Question 34

what are the secondary structures of proteins usually stabilized by?

Answer 34

hydrogen bonds

Question 35

H bonds usually form in the backbone between _____ and ____ groups

Answer 35

N-H and C=O groups

Question 36

What are the two major types of secondary structures?

Answer 36

- Alpha helix and beta sheets

Question 37

It is possible for some parts of protein to not have any ____ secondary structure

Answer 37

"regular"

Question 38

What are hydrogen bonds?

Answer 38

A bond betweeen a hydrogen atom and an electronegative atom (acceptor) such as nitrogen or oxygen, when the hydrogen itself is covalently bonded to another electronegative atom (donor)